Tracks, Busses, Submixes, and the Master Bus

Multitrack projects contain tracks, busses, and submixes. Tracks, busses, and submixes appear as horizontal rows in the Timeline and as vertical channel strips in the Mixer. In both the Timeline and Mixer, tracks, busses, and submixes are grouped together, with a separator between each category. You can move each type within its own category but cannot move it to either of the other categories. Each track, bus, and submix has a header with its icon, name, and a set of controls. The Master bus represents the final mix that goes to physical outputs. The Master bus has no icon or editable name.

Tracks

Tracks contain the audio you add to your project in the Timeline. Each track has a color label, a name, an icon, and a set of controls that appear in the track’s header in the Timeline and in its channel strip in the Mixer. Track controls include a volume slider, a pan control, a submix pop-up menu, and buttons to mute or solo the track, bypass effects, and enable the track for recording. In addition, each channel strip includes level meters you can use to watch the track’s levels and a set of effects slots where you can add and order track effects and sends.

Busses

In Soundtrack Pro, a bus is a separate but parallel audio signal created with a send. A send can tap an audio signal and create a separate signal known as a bus. (Some might call this an auxiliary bus.) Busses can be processed or combined independently of the main signal. They can be combined with other signals in a submix or at the final mix, or they can be routed to altogether separate outputs.

Each bus has a color label, a name, an icon, and a set of controls that appear in the bus’s header in the Timeline and in its channel strip in the Mixer. Bus controls are the same as track controls, except that a bus does not have an Arm for Recording button (because you can’t record audio to a bus). The bus controls affect the audio of every track sent (routed) to that bus.

For example, you could route every dialogue track for a particular actor to a bus with the actor’s name. You could adjust the volume of all the actor’s dialogue using the bus volume fader and add an EQ effect that brings out the actor’s voice in the mix. You could then route that audio bus to a particular submix. The main reason to apply effects this way (rather than directly on the track) is so you can control the amount and characteristics of the effect on multiple tracks using one set of controls.

Submixes

Submixes let you combine the audio from different tracks and busses and route the audio to physical outputs. If you are using external audio hardware that supports multiple physical outputs, you can add submixes to a project and choose the physical output to which each submix routes its audio. For more information about signal routing in Soundtrack Pro, see Basic Signal Routing in Soundtrack Pro.

For example, you could route the audio from the dialogue tracks for each actor to a submix called “Dialogue” and then route all of the dialogue from that submix to a single output jack. You could route all music tracks to another submix and all effects tracks to a third submix. Then you could adjust the volume or add effects separately to each submix. For a final stereo mix, you could route all submixes to the same pair of physical output channels (channels 1 and 2, for example), or to separate outputs. In the case of a surround mix, you could route all submixes to channels 1–6. For a detailed explanation of this example, see Example: Mixing a Project with Submixes.

Each submix has a color label, a name, an icon, and a set of controls that appear in the submix’s header in the Timeline and in its channel strip in the Mixer. Submix controls include a volume slider, a pop-up menu where you can choose the physical output channels for the submix, and buttons to mute or solo the submix and add effects. Each submix channel strip includes level meters you can use to watch the submix’s levels and a set of effects slots where you can add and order effects and sends. Submixes do not have pan controls or Arm for Recording buttons.

The Master Bus

The Master bus represents the final mix from Soundtrack Pro: what will be heard from physical output jacks. On a signal routing basis, the Master bus is practically a mirror image of the connected hardware output device. It has a single volume control but does not have panners. You can apply effects to the Master bus, but you cannot automate those effects. Effects applied to the Master bus are placed across all channels.